管理从url下载的数据-swift

我有两个可以下载数据的URL，这两个URL为我提供了此类json：

(一)

R->

2） //其中id_team param是从第一个URL下载的id

R->

{“image\u team”：[{“id”：4，“img\u path”：“http:\/\/localhost\/MyWebService\/images\/imgTest.png”，“id\u team”：1}

现在，为了下载这些数据，我在swift中创建了包含和下载数据的类和函数

分别位于file.swift文件中的两个类别为：

1） 在TeamJson.swift中：

import Foundation

class ClassJsonTeam: Codable {

    private var teams: [JsonTeam]

    init(teams: [JsonTeam]) {
        self.teams = teams
    }

    func getTeams()-> [JsonTeam]{
        return(self.teams);
    }

    func setTeams(teams:[JsonTeam]){
        self.teams = teams;
    }

}

class JsonTeam: Codable {
    private let id: Int
    private var name: String
    private var member: Int

    init(id: Int, name: String, member: Int) {
        self.id = id
        self.name = name
        self.member = member
    }

    func getId()->Int{
        return(self.id);
    }

    func setId(id:Int){
        self.member = id;
    }

    func getName()->String{
        return(self.name);
    }

    func setName(name:String){
        self.name = name;
    }

    func getMembers()->Int{
        return(self.member);
    }

    func setMembers(members:Int){
        self.member = members;
    }
}

2） 在ImageJsonTeam.swift中

import Foundation

class ClassJsonTeamImage : Codable {
    private var teams : [JsonTeamImg]

    init(teams: [JsonTeamImg]) {
        self.teams = teams
    }

    func getTeamsImg()-> [JsonTeamImg]{
        return(self.teams);
    }

    func setTeamsImg(teams:[JsonTeamImg]){
        self.teams = teams;
    }
}

class JsonTeamImg : Codable{
    private var id : Int
    private var imagePath: URL
    private var teamId : Int

    init(id : Int, imagePath : URL , teamId : Int) {
        self.id = id
        self.imagePath = imagePath
        self.teamId = teamId
    }

    func getId() -> Int{
        return(self.id)
    }

    func setId(id : Int){
        self.id = id
    }

    func  getImagePath() -> URL {
        return(self.imagePath)
    }

    func setImagePath(imagePath : URL){
        self.imagePath = imagePath
    }

    func getTeamId()-> Int{
        return(self.teamId)
    }

    func setTeamId(teamId : Int){
        self.teamId = teamId
    }
}

此外，由于我需要合并来自两个JSON的信息，我创建了第三个此类：

3） CompleteTeamJson.swift

import Foundation

public class ClassJsonCompleteTeam{
    private var team : [JsonCompleteTeam]

    init(team : [JsonCompleteTeam]){
        self.team = team
    }
}

public class JsonCompleteTeam{
    private var id : Int
    private var name : String
    private var member : Int
    private var imgUrl : URL

    init(id: Int, name: String, member: Int, imgUrl: URL) {
        self.id = id
        self.name = name
        self.member = member
        self.imgUrl = imgUrl
    }

    func getId()->Int{
        return(self.id);
    }

    func setId(id:Int){
        self.member = id;
    }

    func getName()->String{
        return(self.name);
    }

    func setName(name:String){
        self.name = name;
    }

    func getMembers()->Int{
        return(self.member);
    }

    func setMembers(members:Int){
        self.member = members;
    }

    func  getImageUrl() -> URL {
        return(self.imgUrl)
    }

    func setImagePath(imgUrl : URL){
        self.imgUrl = imgUrl
    }

}

现在，我的viewController中的情况如下：

import UIKit

//var teamCollection  : ClassJsonTeam!
//
class ViewController: UIViewController {

    @IBAction func InsertNewTeamButton(_ sender: Any) {
        performSegue(withIdentifier: "NewTeamSegue", sender: self)
    }

    var teams: [JsonTeam]?
    var teamsImg : [JsonTeamImg]?
    var teamsComplete : [JsonCompleteTeam]?

    override func viewDidLoad() {
        super.viewDidLoad()

        downloadTeams(completion: { (teams) in

            self.teams = teams

            for index in (0...(self.teams!.count - 1)){

                self.downloadTeamsImage(idTeam: teams[index].getId(), completion:
                    {(teamsImg) in self.teamsImg = teamsImg
                })
                let finalId : Int = teams[index].getId()
                let finalName : String = teams[index].getName()
                let finalMember : Int = teams[index].getMembers()
                var finalURL : URL = URL(string : "http://localhost/MyWebService/images/EmptyImg.png")!

                for index2 in (0...(self.teamsImg!.count - 1)){
                    if (finalId == self.teamsImg![index2].getId()){
                        finalURL = self.teamsImg![index2].getImagePath()
                    }
                }

                let tempCompleteTeam = JsonCompleteTeam(id: finalId, name: finalName, member: finalMember, imgUrl: finalURL)
                self.teamsComplete?.append(tempCompleteTeam)


            }

            //self.InsertNewTeamButton((Any).self)
            self.showTeamButton((Any).self)

        })
    }

    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        // somethings in new wc //
    }


    @IBAction func showTeamButton(_ sender: Any) {
        performSegue(withIdentifier: "TeamListSegue", sender: self)
    }

    func downloadTeams(completion: @escaping (([JsonTeam]) -> Void)) {
        //get teams with classes
        let getTeamUrl = "http://192.168.178.77/MyWebService/api/getteams.php"

        guard let urlTeam = URL(string: getTeamUrl) else { return }
        URLSession.shared.dataTask(with: urlTeam) { (data,response,err) in
            guard let data = data else {return}
            do {
                let team = try JSONDecoder().decode(ClassJsonTeam.self, from: data)
                var tempArrayTeam = [JsonTeam]()
                for index in 0...(team.getTeams().count - 1) {

                    let tempTeam = JsonTeam(id: team.getTeams()[index].getId(),
                                            name: team.getTeams()[index].getName(),
                                            member: team.getTeams()[index].getMembers())

                    print(team.getTeams()[index].getId())
                    print(team.getTeams()[index].getName())
                    print(team.getTeams()[index].getMembers())

                    tempArrayTeam.append(tempTeam)
                }
                completion(tempArrayTeam)
            } catch let jsonErr{
                print("Error serializing json: \(jsonErr.localizedDescription)")
            }
            }.resume()
    }

    func downloadTeamsImage(idTeam: Int,completion: @escaping (([JsonTeamImg]) -> Void)) {
        //get teams with classes
        let getTeamUrl = "http://127.0.0.1/MyWebService/api/fetch_image.php?id_team=\(idTeam)"

        guard let urlTeam = URL(string: getTeamUrl) else { return }
        URLSession.shared.dataTask(with: urlTeam) { (data,response,err) in
            guard let data = data else {return}
            do {
                let team = try JSONDecoder().decode(ClassJsonTeamImage.self, from: data)
                var tempArrayTeamImg = [JsonTeamImg]()
                for index in 0...(team.getTeamsImg().count - 1) {

                    let tempTeamImg = JsonTeamImg(id: team.getTeamsImg()[index].getId(),
                                               imagePath: team.getTeamsImg()[index].getImagePath(),
                                               teamId: team.getTeamsImg()[index].getTeamId())

                    print(tempTeamImg.getId())
                    print(tempTeamImg.getImagePath())
                    print(tempTeamImg.getTeamId())

                    tempArrayTeamImg.append(tempTeamImg)
                }
                completion(tempArrayTeamImg)
            } catch let jsonErr{
                print("Error serializing json: \(jsonErr.localizedDescription)")
            }
            }.resume()
    }

}

让我们直截了当地说：如果我单独调用这两个函数，它们当然可以工作，但我不知道如何将下载的数据合并到do catch中（例如在双变量团队和teamsImg中）因此，我们可以贡献变量teams完成并在另一个视图控制器中传输数据

---

提前感谢：D

更新您的

viewDidLoad

 override func viewDidLoad() {
        super.viewDidLoad()

        downloadTeams(completion: { (teams) in

            self.teams = teams

            for index in (0...(self.teams!.count - 1)){
                self.downloadTeamsImage(idTeam: teams[index].getId(), completion:
                    {(teamsImg) in self.teamsImg = teamsImg

                let finalId : Int = teams[index].getId()
                let finalName : String = teams[index].getName()
                let finalMember : Int = teams[index].getMembers()
                var finalURL : URL = URL(string : "http://localhost/MyWebService/images/EmptyImg.png")!

                for index2 in (0...(self.teamsImg!.count - 1)){
                    if (finalId == self.teamsImg![index2].getId()){
                        finalURL = self.teamsImg![index2].getImagePath()
                    }
                }

                let tempCompleteTeam = JsonCompleteTeam(id: finalId, name: finalName, member: finalMember, imgUrl: finalURL)
                self.teamsComplete?.append(tempCompleteTeam)

                // YOU CAN MOVE FORWARD NOW AS ALL THE DATA IS LOADED 
                if index == self.teams!.count - 1 {
                   self.showTeamButton((Any).self)
                }

             }
           })

        })
    }

---

这将删除崩溃，并在加载所有数据时调用

showTeamButton

您已将所有数据设置在所需的变量中，您可以使用这些数据做任何您想做的事情，并且可以在任何地方访问它们，您的问题是什么？@Razitwana问题是datatask在另一个线程上工作，因此，在viewDidLoad中，我应该在函数完成下载数据之前等待，然后才能使用这些函数执行操作。事实上，应用程序在这一行中崩溃了：对于（0…（self.teamsImg！.count-1））中的index2{错误是：线程5：致命错误：在解包可选值时意外发现nil首先，它应该在那里崩溃，因为您的

self.teamsImg

此时为nil。其次，您应该在问题中提到这一点。现在您只需在完成时移动此代码。假设这是这里唯一的问题。是否指向ab在这里输出操作依赖项？例如，当数据从两个操作准备就绪时，是否希望收到通知？

 override func viewDidLoad() {
        super.viewDidLoad()

        downloadTeams(completion: { (teams) in

            self.teams = teams

            for index in (0...(self.teams!.count - 1)){
                self.downloadTeamsImage(idTeam: teams[index].getId(), completion:
                    {(teamsImg) in self.teamsImg = teamsImg

                let finalId : Int = teams[index].getId()
                let finalName : String = teams[index].getName()
                let finalMember : Int = teams[index].getMembers()
                var finalURL : URL = URL(string : "http://localhost/MyWebService/images/EmptyImg.png")!

                for index2 in (0...(self.teamsImg!.count - 1)){
                    if (finalId == self.teamsImg![index2].getId()){
                        finalURL = self.teamsImg![index2].getImagePath()
                    }
                }

                let tempCompleteTeam = JsonCompleteTeam(id: finalId, name: finalName, member: finalMember, imgUrl: finalURL)
                self.teamsComplete?.append(tempCompleteTeam)

                // YOU CAN MOVE FORWARD NOW AS ALL THE DATA IS LOADED 
                if index == self.teams!.count - 1 {
                   self.showTeamButton((Any).self)
                }

             }
           })

        })
    }